Integrated cavity backed slot array antenna system

Abstract

An antenna system includes a substrate of a dielectric material. A conductive layer defines a feed slot joins a number of side slots arranged in a line forming an array. The side slots are spaced from one another and the conductive layer is disposed on the substrate. The array is configured to radiate a radiation pattern characterized by a first beam width in a first plane and a second beam width in a second plane perpendicular to the first plane, wherein the first beam width is wider than the second beam width.

What is claimed is: 
     
       1. An antenna system, comprising:
 a substrate of a dielectric material; and 
 a conductive layer disposed on the substrate and defining a feed slot joining a number of side slots arranged in a line forming an array, the side slots spaced from one another; 
 wherein the array is configured to radiate a radiation pattern characterized by a first beam width in a first plane and a second beam width in a second plane perpendicular to the first plane, wherein the first beam width is wider than the second beam width, 
 wherein the substrate is configured as an interposer, 
 wherein the array is configured to radiate the radiation pattern through the interposer. 
 
     
     
       2. The system of  claim 1 , wherein the conductive layer has first and second sides and comprising:
 a first ground plane disposed on the first side of the array and spaced apart from the array; and 
 a number of conducting pillars grounding the substrate to the first ground plane, 
 wherein the conducting pillars define a second ground plane on the substrate, 
 wherein the conducting pillars do not extend through the substrate. 
 
     
     
       3. The system of  claim 2 , wherein the substrate is disposed on the second side of the array. 
     
     
       4. The system of  claim 2 , wherein the first ground plane, the conductive pillars and the second ground plane define an air cavity configured to prevent back radiation in a direction outward from the first side of the substrate. 
     
     
       5. The system of  claim 1 , comprising a number of conducting pillars grounding the substrate to the first ground plane, wherein the conducting pillars define a second ground plane on the substrate, wherein the conducting pillars do not extend through the substrate. 
     
     
       6. The system of  claim 1 , comprising a dielectric layer disposed on the conductive layer, wherein the conductive layer disposed on the substrate and defining a feed slot joining a number of side slots arranged in a line forming an array, the side slots spaced from one another, wherein the conductive layer defines an opening between each of the side slots and the feed slot, wherein the respective opening between at least one of the side slots and the feed slot is smaller than the respective opening between another of the side slots and the feed slot. 
     
     
       7. The system of  claim 1 , comprising a coplanar waveguide configured to launch a signal to the feed slot. 
     
     
       8. The system of  claim 7 , comprising;
 a ground plane spaced apart from the array; and 
 a front end module configured to generate a signal and to deliver the signal to the coplanar waveguide, wherein the front end module is disposed between the conductive layer and the ground plane. 
 
     
     
       9. The system of  claim 8 , comprising a radio frequency printed circuit board, wherein the ground plane is disposed on the radio frequency printed circuit board. 
     
     
       10. The system of  claim 9 , comprising a transceiver module disposed on the radio frequency printed circuit board and coupled with the array through the front end module and the substrate. 
     
     
       11. An antenna system, comprising:
 a substrate of a dielectric material; and 
 a conductive layer disposed on the substrate and defining a feed slot joining a number of side slots arranged in a line forming an array, the side slots spaced from one another; 
 wherein the conductive layer defines an opening between each of the side slots and the feed slot, 
 wherein the respective opening between at least one of the side slots and the feed slot is smaller than the respective opening between another of the side slots and the feed slot, 
 wherein the array is configured to radiate a radiation pattern characterized by a first beam width in a first plane and a second beam width in a second plane perpendicular to the first plane, wherein the first beam width is wider than the second beam width. 
 
     
     
       12. The system of  claim 11 , wherein the conductive layer has first and second sides and comprising:
 a first ground plane disposed on the first side of the conductive layer and spaced apart from the conductive layer; and 
 a number of conducting pillars grounding the substrate to the first ground plane, 
 wherein the substrate is disposed on the second side of the conductive layer, 
 wherein the conducting pillars define a second ground plane on the substrate, 
 wherein the conducting pillars do not extend through the substrate. 
 
     
     
       13. The system of  claim 12 , comprising:
 a coplanar waveguide configured to launch a signal to the feed slot; and 
 a front end module configured to generate a signal and to deliver the signal to the coplanar waveguide, wherein the front end module is disposed between the conductive layer and the first ground plane. 
 
     
     
       14. The system of  claim 12 , wherein the second ground plane comprises a silicon material, is defined on the substrate and is bounded by the conductive pillars, wherein the first ground plane, the conductive pillars and the second ground plane define an air cavity configured to prevent back radiation in a direction outward from the first side of the substrate. 
     
     
       15. The system of  claim 11 , comprising a second feed slot connected with an additional number of side slots. 
     
     
       16. The system of  claim 11 , wherein the substrate is configured as an interposer through which the array is fed a signal, wherein the array is configured to radiate the radiation pattern through the interposer, wherein the first beam width extends in an azimuth direction relative to the vehicle and the second beam width extends in an elevation direction relative to the vehicle. 
     
     
       17. The system of  claim 11 , comprising a dielectric layer disposed on the conductive layer. 
     
     
       18. The system of  claim 11 , comprising:
 a transmitter coupled with the array; 
 a radio frequency printed circuit board through which the array is coupled with the transmitter; and 
 a ground plane disposed on the radio frequency printed circuit board; 
 wherein the ground plane is spaced away from the substrate. 
 
     
     
       19. The system of  claim 11 , comprising a number of conductive pillars surrounding the array and contacting the substrate. 
     
     
       20. An antenna system for a radar of a vehicle, the system comprising:
 a substrate of a dielectric material; 
 a conductive layer disposed on the substrate and defining a feed slot joining a number of side slots arranged in a line forming an array through the conductive layer, the side slots spaced from one another and the array disposed on the substrate, the conductive layer having first and second sides; 
 a coplanar waveguide configured to launch a signal to the feed slot; 
 a first ground plane disposed on the first side of the conductive layer and spaced apart from the conductive layer; 
 a number of conducting pillars grounding the substrate to the first ground plane; and 
 a second ground plane of a silicon material defined on the substrate and bounded by the conductive pillars, 
 wherein electromagnetic energy is radiated by the array as a result of travelling waves that travel along the feed slot, 
 wherein the array is configured to radiate a radiation pattern characterized by a first beam width in a first plane and a second beam width in a second plane perpendicular to the first plane, wherein the first beam width is wider than the second beam width, 
 wherein the first beam width extends in an azimuth direction relative to the vehicle and the second beam width extends in an elevation direction relative to the vehicle.